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INFO: rcu detected stall in sys_io_setup (2)

Status: auto-obsoleted due to no activity on 2026/04/03 13:04
Subsystems: fs
[Documentation on labels]
First crash: 103d, last: 103d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
ecf83845-239e-4782-9875-ea846c01357c repro INFO: rcu detected stall in sys_io_setup (2) 2026/03/08 11:42 2026/03/08 11:42 2026/03/08 11:51 31e9c887f7dc24e04b3ca70d0d54fc34141844b0
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_io_setup mm cgroups 1 1 675d 675d 0/29 auto-obsoleted due to no activity on 2024/09/08 23:15

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P30824/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=160553, q=256 ncpus=2)
task:syz.1.6702      state:R  running task     stack:26472 pid:30824 tgid:30821 ppid:24386  task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline]
RIP: 0010:lock_is_held_type+0x57/0x150 kernel/locking/lockdep.c:5936
Code: 85 c0 0f 85 ce 00 00 00 65 4c 8b 25 db a9 3a 08 41 8b 94 24 2c 0b 00 00 85 d2 0f 85 b6 00 00 00 48 89 fd 41 89 f6 9c 8f 04 24 <fa> 48 c7 c7 a9 eb bb 8d 4d 8d ac 24 30 0b 00 00 45 31 ff e8 01 19
RSP: 0018:ffffc9000c71fbb0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc9000c71fc90 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88807791b3f0
RBP: ffff88807791b3f0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff88801eed8b30 R12: ffff88801eed8000
R13: 00000000ffffffff R14: 00000000ffffffff R15: 0000000000100dc0
 lock_is_held include/linux/lockdep.h:249 [inline]
 xa_head include/linux/xarray.h:1210 [inline]
 xas_start+0x458/0x790 lib/xarray.c:191
 xas_load+0x22/0x5b0 lib/xarray.c:239
 filemap_get_entry+0x109/0x3b0 mm/filemap.c:1895
 __filemap_get_folio_mpol+0x5d/0xc60 mm/filemap.c:1941
 __filemap_get_folio include/linux/pagemap.h:763 [inline]
 aio_setup_ring fs/aio.c:524 [inline]
 ioctx_alloc+0x788/0x2230 fs/aio.c:792
 __do_sys_io_setup fs/aio.c:1399 [inline]
 __se_sys_io_setup fs/aio.c:1382 [inline]
 __x64_sys_io_setup+0xc9/0x230 fs/aio.c:1382
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98d3b8f749
RSP: 002b:00007f98d4a21038 EFLAGS: 00000246 ORIG_RAX: 00000000000000ce
RAX: ffffffffffffffda RBX: 00007f98d3de6090 RCX: 00007f98d3b8f749
RDX: 0000000000000000 RSI: 0000200000000800 RDI: 0000000000010000
RBP: 00007f98d3c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98d3de6128 R14: 00007f98d3de6090 R15: 00007ffc3c698728
 </TASK>
rcu: rcu_preempt kthread starved for 10132 jiffies! g160553 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28248 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: c6 5f 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 13 49 12 00 fb f4 <e9> cc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197de8 EFLAGS: 000002c6
RAX: 000000000633e6a5 RBX: 0000000000000001 RCX: ffffffff8b7816d9
RDX: 0000000000000000 RSI: ffffffff8dace4f3 RDI: ffffffff8bf2b480
RBP: ffffed1003b56498 R08: 0000000000000001 R09: ffffed10170a673d
R10: ffff8880b85339eb R11: ffff88801dab2ff0 R12: 0000000000000001
R13: ffff88801dab24c0 R14: ffffffff9088b9d0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881249f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb79ef3360c CR3: 0000000033d74000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x38d/0x510 kernel/sched/idle.c:332
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x148
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/03 13:02 upstream 805f9a061372 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_io_setup
* Struck through repros no longer work on HEAD.